This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. To test the hypothesis that neural precursor cells differentiated from embryonic stem cells and transplanted into the brain [unreadable] alleviates Parkinsonian symptoms in nonhuman primates.[unreadable] [unreadable] Hemi-parkinsonian symptoms were induced by MPTP injection. Neural precursor cells differentiated from human or rhesus [unreadable] embryonic stem cells were transplanted into the striatum and substantia nigra. Sham control animals received the same [unreadable] surgery, but no neural precursor cells. Results suggested that transplantation of neural precursor cells survived for up to 5 [unreadable] months, transformed into dopamine neurons, and alleviated Parkinsonian symptoms. These preliminary observations show [unreadable] potential use of embryonic stem cells for human clinical treatments. This research used Animal Services and Research [unreadable] Services.